D.1. Linux Devices

In Linux various special files can be found under the directory
/dev. These files are called device files and
behave unlike ordinary files. The most common types of device files
are for block devices and character devices. These files are an
interface to the actual driver (part of the Linux kernel) which in
turn accesses the hardware. Another, less common, type of device file
is the named pipe.
The most important device files are listed in the tables below.

fd0

First Floppy Drive

fd1

Second Floppy Drive

hda

IDE Hard disk / CD-ROM on the first IDE port (Master)

hdb

IDE Hard disk / CD-ROM on the first IDE port (Slave)

hdc

IDE Hard disk / CD-ROM on the second IDE port (Master)

hdd

IDE Hard disk / CD-ROM on the second IDE port (Slave)

hda1

First partition of the first IDE hard disk

hdd15

Fifteenth partition of the fourth IDE hard disk

sda

SCSI Hard disk with lowest SCSI ID (e.g. 0)

sdb

SCSI Hard disk with next higher SCSI ID (e.g. 1)

sdc

SCSI Hard disk with next higher SCSI ID (e.g. 2)

sda1

First partition of the first SCSI hard disk

sdd10

Tenth partition of the fourth SCSI hard disk

sr0

SCSI CD-ROM with the lowest SCSI ID

sr1

SCSI CD-ROM with the next higher SCSI ID

ttyS0

Serial port 0, COM1 under MS-DOS

ttyS1

Serial port 1, COM2 under MS-DOS

psaux

PS/2 mouse device

gpmdata

Pseudo device, repeater data from GPM (mouse) daemon

cdrom

Symbolic link to the CD-ROM drive

mouse

Symbolic link to the mouse device file

null

Anything written to this device will disappear

zero

One can endlessly read zeros out of this device

D.1.1. Setting Up Your Mouse

The mouse can be used in both the Linux console (with gpm) and the X
window environment. Normally, this is a simple matter of installing
gpm and the X server itself. Both should be
configured to use /dev/input/mice as the mouse
device. The correct mouse protocol is named exps2
in gpm, and ExplorerPS/2 in X. The respective
configuration files are /etc/gpm.conf and
/etc/X11/xorg.conf.

Certain kernel modules must be loaded in order for your mouse to work.
In most cases the correct modules are autodetected, but not always for
old-style serial and bus mice[18], which are quite rare except on very old computers. Summary
of Linux kernel modules needed for different mouse types:

Module

Description

psmouse

PS/2 mice (should be autodetected)

usbhid

USB mice (should be autodetected)

sermouse

Most serial mice

logibm

Bus mouse connected to Logitech adapter card

inport

Bus mouse connected to ATI or Microsoft InPort card

To load a mouse driver module, you can use the modconf
command (from the package with the same name) and look in the category
kernel/drivers/input/mouse.

[18]
Serial mice usually have a 9-hole D-shaped connector; bus mice have an
8-pin round connector, not to be confused with the 6-pin round connector
of a PS/2 mouse or the 4-pin round connector of an ADB mouse.